Manufacture of aromatic selenium compounds



Patented Feb. 19,1935 1,991,646

M NtiFAoTURE F AROMATIG SELENIUM COMPOUNDS Alexander I. Wuertz; Carrollville, Donald P. Gra- I e ham S outb Milwaukee and Melvin A. Perkins, Milwaukee, Wis., assignors toE. Iedu. Pont de 7 v Nemours &e Company, Wilmington, Dele, a corporationof Delaware Y 'NoDrawing; q ApplicationfMarch 27, 1933,, v

Serial No:. 66 2 ,996 I I V 146laims 1 (01. 260 -61) -This invention relates to'themanufactureof :that a great. deal; of the trouble is apparentearomatic selenium compounds. EMore p'articuly dueeto thefact that-theadded metal generates larly, this invention e deals with-an improved hydrogen rapidly, which buoys up the. metal, :process for the manufacture of aromatic 'selenols causing it to float on the surface of thecharge 5 and related compounds by replacement o'fhaloandxpreventing-it from getting intimately mixed 5 gen in aromatic halogen compounds by selenium. with the selenium. Another 'cause for difliculty It is an object of 'this invention to provide an eis ethe action "of the highly concentrated alkali economical and efficient process for the manuon=the halogen-anthraquinone or -benzanthrone facture of aromatic selenols and selenolates. body, splittingoff halogen; and converting the v Other and further important objects of this in- Organic body intb 'afmm which isless readily l0 vention-will appear asthedescription proceeds. attacked, by sodiumselenide. e I l Of the aromatic selenolsand dise'lenides, those =In the same, eopending applications is also of the anthraquinoneeand benzanthrone series disclosed a process involvingfirst the formaare of particular commercial interest We shall tion of al kali metal selenide in aqueous or altherefore confine our discussion hereinafter t0 Q }(fl ,1l ;O S SuSpenSimIandUthen adding the 15 these compounds and designate them generieally vgq ig t l q a d -k e s eh we i not y as compounds of the anthraquinoneseriese But e satisfactory either, for the reason that sodium it shouldbe understoodethat our inventionfis of eand'p assiumselenid a highly ab bOdieS a general nature; and applies to themanufacand; tend to form complex polyselenides which ture ofother:aromaticwselenols and diselenides, are not very active as :selenizing agents. 1 1 -20 Where a halogen atom on the aromatic nucleus We have now'invented a new process of operais replaced by selenium}: e tion which obviates all the above difficulties and p The manufacture. of, anthraquinone selnols gives excellent yieldson a large scale as well as was'first described in German Patent-No. 264,941. in the laboratory." Our novel process has the This patent proposed to use sodium or po'tasfurther advantage that it works well with the ;-25

. sium selenide as the selenizing agent, and in turn simpler aryl-halogen derivatives, for instance, 1- obtained this agent by passing hydrogen selenide eor 2-halogenanthraquinones, whereas the proc- ;into an aqueous alcoholic solution of sodium 'or esses of the mentioned copending applications are potassium hydroxide. The disadvantage inthis not applicable to such simple compounds. Our

process isthat it requires generation of hydrogen .novel process also has the advantages of fa- 30 1'35 wasteful and costly.-

selenide which is a highly poisonous gas. It cili'ty of control andreduced hazard of operation.

. appears also that this-process consumes three "According toour novelprocess; the halogenated times as much selenium as I actually, combines aromatic compound in which it is desired to' rewith the anthra quino'nenucleus'and is therefore place the halogen withselenium, is slurried in v e I alcohol, alcohol mixe d with water, or water alone,

In copending applications, Perkins and Bishop, together with powdered selenium or selenium Ser. No. szqgzzaandrer ins, sere Nepalese, e ide/ n 'i a sufficiently fi state it is proposed to manufacture therequired sodi- ;of division. to avoid settling, p'referablyin the urn selenide in situ, by feeding in graduallya form of grains epassingea lofbut not a 20 mesh 40 metal which stands high" in "the electromotive screen' T is miXtHIBiS a tated at 6080 C. and. 40

seriesinto an aqueous or alcoholic aqueous mix a solution of an alkali hydroxide is added over a tureicontaining "the organic halide tolbe seleperi d of several hours? h c p is es t e nized, elemental selenium and causticsbda, 111 same result as'those processes in which vthe rethe formerof' the two applications this process duci g metal s added t0 h alkaline slurry of is applied to the manufacture of 2-a m ino-anthe halogenated inte diate a d sel ium; but 45 thraquinone-l-selenol'sjinthe latter, to the manavoids the possibilityof concentration of the re- :ufacture of Bzl-benzanthrone-selenols.e The 'reducing metal near the surfaceof the charge and ducing metere pm' ed'e s either sodium or alualso eliminates the undesirable I effects of. exminum." This process jconstitutes a considercess alkali on the intermediate. The sodium alu- '50 able improvement overf the process, of, German lr'nihate formed during the first p t Of the re 5 Patent No. 264,941,.biit it still suffers from the action together with aluminum hydroxide serve dravvback that in large scale operation theyields v to stabilize the alkalinity of the charge ata point .are' not sohigh as would be expeeted from the below'that capable of damaging theintermediate indications of laboratory experiments it is only after the aluminum is all con- We haveflinvestigatedjhis process and i und sumed and the intermediate converted 55 "tion.

procedure, the following examples in which parts by weight are given will serve to" illustrate our preferred mode of operation. 1

Example 1 A mixture of 100 parts oi l-chlor-2-aminoanthraquinone, 33.3 parts of selenium powder,

and 11 parts of aluminum (powder or grains) is I suspended in 280 parts of alcohol and 100 parts of water. The suspension is heated to 70-f75 .C. and at this temperature, a solutionof 83 parts of sodium hydroxide in 166 parts of water is added overa period of from 2 to 6 hours.

parts of saturated saltsolution, allowedto cool 'to room temperature, andfiltered; The cake is washedwitha 15' per cent salt solution until The product, -2-amino- V 30.9 partsof Bzl bromo-benzanthrone',8.7'parts of selenium'and 3 parts of aluminumigrains) mixed and introduced into 100 parts alcohol.) The slurry istheatedto -70" C. and at this the filtrate is clear. anthraquinone-l sodium selenolate is isolated in the form of dark blue needles-soluble in water to give a blue-violetsolution. It may be oxidized to 2,2"-diamino-1,1-dianthraquinonyl diselenide by the action of air on a water suspension of the 'selenolate or by the use of some other oxidizing agent such: as nitrobenzene-meta-sodium-sulfonate. The diselenide may also'be prepared by oxidizing directly the reflux mass prior to and in lieu of salting out. In either case, the diselenide Example? A mixture of 242 parts of lchloro-anthraquinone, 87 parts selenium powder, and 30 parts aluminum (grains) is suspended in 1000 parts ethyl alcohol and the suspension warmed to about C. While maintaining the temperature' at 70-78 C., and under good agitation, a

2 solution of 350 parts potassium hydroxide in 800 "parts of water isadded at a uniform rate over a period of about four hours. The mass is then refluxed for about one hour longer, or until no crystals of unchanged l-chloro-anthraquinone are visible in'a'test sample under the microscope. At this point, the potassium anthraquinone selenolate' may be isolated by salting out (KCl) andwashing; 'A preferred procedure, however, is to convert the mass directly into the diselenide and to isolate the latter. For this purpose the reaction mass is diluted with water and oxidized f' by blowing air. through the same, or by adding a mild oxidizing agent such as potassium ferricyanide. In either case a bright orange yellow solid precipitates, which may be isolated by filtra- It can be freed of a small proportion of free selenium'by extraction with neutral sodium sulfite solution. The product is halogen-free, contains 7 about 26% selenium and gives an orange-red solution in sulfuric acid. It appears to be idenfftical with the dianthraquinonyl-diselenide obtained according to Example 2 of German Patent No. 264,9 i1, and is obtained in nearly quantitative The charge is then refluxed at -80 C. for 2 hours or until 'a sample on a microscope slide shows no -more yellow material. It is then salted 'with 500 Example 3 A mixture of 28.! parts of 2-bromo-anthraquinone, 8.7 parts of selenium powder, and 3 parts of aluminum grains is introduced-into100 parts of ethyl alcohol and the slurry-heated to 70 C. A solution of 25 parts of sodium hydroxide in parts of water is added uniformly over a period of four hours, the temperature being maintained at YO-75C. The mass is then heated to reflux for an hour, diluted with an equal volume of hot water, filtered and the very small amount of residual insoluble material washed with warm water to extract all remaining selenolate. The filtrate and washings are of an intense red-violet color.

cipitate which becomes orange-yellow upon drying. s The dry product gives a strong red-violet colorationin sulfuric acid. It is obtained as bright yellow needles by recrystallization ,from

nitrobenzene and contains the theoretical proportion .of seleniunufor Z-anthraquinone-jselnol;

Acidification gives a yellowish-green pre- It melts' at about 264 C. and is apparently. iden- .ticalwith the product of Example 1 of German Patent No.-2 64,941.

I Erample4 water is added over a periodoi' 2 hours. Toward the endofthisprocedure the temperature is.

allowedto-rise to reflux point and is maintained at this temperature for hour. Upon'dilution with an equal volume of hot water and filtration. I 7' toremove a small proportionof Bzl,Bzl-dibenzanthronyl selenide, an intense violet solution'oi' potassium" Bzl-benzanthrone-selenolate is ob-' tained. The filtrate is readilyoxidized to a dull J yellow solid by aeration, which is most probably may be reduced by sodium sulfide solution to give a solution of the sodium salt of Bzl-benzan- Bzl,Bzl-dibenzanthronyl-diselenide. "The latter throne-selenol which may be salted out as'violet solution with an intense violet color and 'iuric acid with a darlr reddish-blue color.

Itwill be understood that'many variations and modifications are possible in our preferred mode of operation without departing from the spirit of this invention. For instance, insteadof selenium,

an equivalent quantity of selenium oxide -or selenious acid maytbe used, since th'esewill be readily reduced under the'conditions above de-' scribed. Instead of ethyl alcohol, other alcohols may beused, for instance, methylalcohol. Numerous 'other variations may be practiced within the spirit ofthis invention, as will be readily understood by those skilled 'in the art.

We claim? 1 r compound which comprises suspending an organichalide of the anthraquinone series in an alcoholic medium together witha reducing metal and a compoundof the groupconsistingoi selenium, its oxidesa'nd its oxy-acids-warming "up the mass, and adding gradually a solution of a caustic alkali. r r

2. The process of producing anra'ryl-selenol lxThe process of producing-an aryI- -seIenOl compound which comprises suspending an organic halide of the anthraquinone series in an alcoholic medium together with selenium and aluminum, heating the mass to about 60- -80 C.

and adding an aqueous solution of a caustic altrated aqueous solution, over a period of about kali.

of the anthraquinone series which comprisessuspending a halogen compound of the anthraquinone series in an alcoholic medium in the presence of finely divided selenium and aluminum, heating the mass to a temperature between 60 and 80 C. and adding gradually an aqueous solution of a caustic alkali.

4. The process of producing an anthraquinoneselenolate, which comprises suspending an an-.

thraquinone-halide in an alcoholic medium in the presence of finely divided selenium and aluminum, heating the mass to a temperature between 60 and 80 C., and adding gradually an aqueous solution of a caustic alkali.

5. The process of producing a Bzl-benzanthrone-selenolate, which comprises suspending a Bzl-benzanthrone-halide in an alcoholic medium in the presence of finely divided selenium and aluminum, heating the mass to a temperature between 60 and 80 C. and adding gradually an aqueous solution of a caustic alkali.

6. A process for preparing a l-selenium derivative of 2-amino-anthraquinone, which comprises suspending substantially 100 parts of 1-chloro-2- amino-anthraquinone, 33 parts of selenium powder, and 11 parts of finely divided aluminum in 280 parts of alcohol and 100 parts of Water, heating the mass to about 70-75 C., adding gradually a solution of substantially 83 parts of sodium hydroxide in 166 parts of water over a period of 2 to 6 hours, and refluxing the mass until a test sample shows no more yellow material.

"7. A process asin claim 6, in which the final mass is diluted with a concentrated salt solution to precipitate 2-amino-anthraquinone-1-sodiumselenolate. I

8. A process as in claim 6, in which the final mass is oxidized to precipitate 2,2-diamino-1,1'- dianthraquinonyl diselenide.

9. A process of preparing a Bzl-selenium derivative of benzanthrone which comprises suspending substantially equivalent proportions of 3. The process of producing an aryl-selenolate Bzl-bromo-benzanthrone and selenium and an excess of aluminum in a quantity of alcohol suifi cient to produce a slurry, heating the mass to about 65-70 C., adding gradually an excess of potassium hydroxide in the form of a concen- 2 hours, and continuing the heating until the reaction is substantially complete.

10. A process as in claim 9, in which the final mass is diluted, filtered and aerated to precipitate Bzl,Bzl-dibenzanthronyl-diselenide.

I 11. In the process of preparing an anthraquinone-selenol compound by reacting an anthraquinone-halide with selenium in the presence of a reducing agent and an alkali in aqueous alcoholic medium, the step which comprises first mixing the anthraquinone-halide, selenium, reducing agent and suspending medium and then adding the alkali.

12. In the process of preparing a benzanthroneselenol compound by reacting 'a benzanthronehalide with selenium in the presence of a reducing agent and an alkali in aqueous-alcoholic medium, the step which comprises first mixing the benzanthrone-halide, selenium, reducing agent and suspending medium and then adding the alkali.

13. In the process of preparing an anthraquinone-selenol compound by reacting an anthraquinone-halide with selenium in the presence of a reducing agent and an alkali in aqueous-alcoholic medium, the step which comprises first mixing the anthraquinone-halide, selenium, reducing agent and suspending medium and then feeding in a solution of the alkali at a rate insufficient to cause violent reaction.

14. In the process of preparing -a benzanthrone-selenol compound by reacting a benzanthrone-halide with selenium in the presence of a reducing agent and an alkali in aqueous-alcoholic medium, the step which comprises first mixing the benzanthrone-halide, selenium, reducing agent and suspending medium and then feeding in a solution of the alkali at a rate insuificient to cause violent reaction. 

